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In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
I am the
Board member responsible for managing a common heating system for an 18-unit
condo in Boston - 3 units across for six floors and about 36,000 squ ft of
interior space . We currently have a
steam-system using a forced-draft boiler sized for 1,987 MBH gross output and
6,427 sqft steam.
had noise, performance and efficiency concerns regarding this present boiler --
and have received a proposal from a reputable heating contractor to replace the
system with a condensing hot-water system.
There are significant costs to tearing up everyone's to re-pipe for hot
water and a rationale we have been given for taking these costs is a
significant annual savings in fuel.
This hydronic-system proposal sizes for (3) boilers ganged
to provide a combined 1,140 MBH gross output -- about 60% of that of our
current system. I realize that a
condensing boiler operates at a higher efficiency than our forced-draft boiler
-- but the uptick in thermal efficiency from 83% to 96% is only a +15% jump.
been told that the remaining efficiency gain (40% - 15% = 25%) is due to the
operating characteristics of delivering hot-water versus steam heat. I don't find anyone on the Web promoting
such an operational difference between the two types of heat.
seeing a proposal to convert from a grossly over-sized existing boiler -- or
have I missed something in the literature about the special efficiencies of
hot-water over steam heat?
your help on this -- Jim Charnley